The present invention relates to provided a source of a gaseous, gas borne or droplet substance.
Such sources are used for dispensing medicaments in metered doses via a dispenser. There is an increasing desire for the number of doses dispensed and/or left in the source to be counted, so that a user can know the number of doses remaining before a fresh source (and dispenser) is required.
The object of the present invention is to provide a substance source with an integral counter.
The Invention
According to a first aspect of the invention there is provided a source of a gaseous, gas borne or droplet substance having:                an inner pressurised container,        a substance-release valve device sealed across an end of the container,        a spout displaceable inwards of the container against a spring of the valve device for substance release,the source also including:        an outer enclosure enclosing the inner container along its length, at least partially across its end remote from the spout and partially at its spout end,                    the outer enclosure and the inner container being arranged to react force for displacement of the spout on substance release;                        a counter accommodated within the outer enclosure for counting substance release displacements of the spout; and        a window in the outer enclosure for viewing the count of the counter.30        
In certain embodiments, the counter is arranged at the end of the outer enclosure, for reacting and counting occurrences of spout-displacement force from the inner container to the outer enclosure. In particular where the substance is a high value medicament, the counter can be a single use electronic counter. However, since an electronic counter is a relatively expensive component of a medicament source, in the preferred embodiment with such a counter, it can be a multi-use electronic counter, with the outer enclosure being provided with a frangible enclosure for the counter, whereby the counter can be removed from the medicament source by breaking the enclosure when it is has reached its normal dose count limit, reset and installed on a fresh source using its fresh frangible closure. In this case, the counter provides the sole abutment for the inner container as regards spout-displacement force, whereby residual medicament cannot be used once the counter has been removed.
Again, the counter can be a removable or an irremovable mechanical counter. The mechanical counter can include a dual set of ratchet teeth and pawls, with angular incrementation determined by the ratchet teeth and can be housed within the outer enclosure and gearing is provided between an incremented ratchet disc and an indicator disc viewable through the window in the outer enclosure. This avoids unreliable dosing with the container being nearly empty.
In other embodiments, the counter is arranged to be incremented by displacement of the spout. Normally such a counter will be a mechanical counter including a rotatable member indexed by one increment on each displacement of the spout.
Such a mechanical counter can include a dual set of ratchet teeth and pawls, one of either of the teeth and the pawls being displaced with the spout the other being fast with the outer enclosure and the rotatable member being incremented partially by one of the dual set of teeth on inwards displacement of the spout and partially by the other of the dual set of teeth on return outwards displacement of the spout.
Alternatively, the mechanical counter can include a single set of ratchet teeth and at least one pawl and a frictional member restraining the rotatable member, one of either of the teeth and the pawls being displaced with the spout the other being fast with the outer enclosure and the rotatable member being incremented by the pawl and teeth on inwards displacement of the spout and held by the frictional member on return outwards displacement of the spout.
In one of these embodiments:                the rotatable member is a portion of the inner pressurised container or a sleeve fast with the container, the container or the sleeve being adapted to be indexed by one increment on each displacement of the spout,        the said portion or sleeve has a helical track,        the window extends axially and/or circumferentially of the outer enclosure and        the source includes an indicator adapted to co-operate with the helical track for indicating movement along the extent of the window.        
Alternatively:                the rotatable member is a member internal of the outer enclosure, extending around the inner container and having a helical track,        the window extends axially and/or circumferentially of the outer enclosure and        the source includes an indicator adapted to co-operate with the helical track for indicating movement along the extent of the window.        
In this alternative, the indicator can have:                a curved inner face engaging the rotatable member, both at the track for movement of the indicator and laterally for location of the indicator and        a flat outer face engaging the window with lateral extent for locating the indicator in the window circumferentially of the outer enclosure.        
Again the indicator can have:                a plain inner face engaging the helical track,        a sprung outer face engaging the window and        sides for locating the indicator in the window circumferentially of outer enclosure andthe window is provided at a groove with sides co-operating with the sides of the indicator in locating the indicator circumferentially of the outer enclosure.        
Thirdly, the indicator and the outer enclosure can have a complementary non-circular cross-section for locating the indicator in the window circumferentially of the outer enclosure.
It is possible for one of the sets of teeth and pawl(s) or the frictional member, whichever is provided, is arranged at the end of the inner member having the helical track remote from the spout and co-operates with the end of the outer enclosure on incrementing of the inner member. However, usually, both sets of teeth and pawls are provided at the spout end of the outer enclosure.
The member having the helical track can essentially comprise the helical track along the extent of the track and around the inner container and is resilient for movement of its spout end with the spout. However, usually, the member having the helical track comprises a circular cylindrical member around the inner container. The helical track itself can be a channel or groove in the cylindrical member. Alternatively, the helical track can be a rib or ridge on the cylindrical member.
In another feature, the member having the helical track, the indicator and the window are all adapted for plunging movement of the member and the indicator with the spout, a return spring being provided for return movement on outwards movement of the member and indicator after inwards, dispensing movement. Alternatively, the member having the helical track is axially located with respect to the outer enclosure and a separate member plungeable with respect to the outer enclosure is provided, the plungeable member being adapted for driving the helical track member in rotation.
Preferably, wherein the plungeable member is provided with:                means for irrotationally locating it with respect to the outer enclosure and        ones of the pawls or the teeth for rotationally driving the helical track member, the others of the teeth or the pawls being provided on the helical track member.In this case, the pawls can be resilient axially of the helical track member for return of the plungeable member.        
Alternatively the plungeable member can be provided with:                the ones of the pawls or the teeth for rotationally driving the plungeable member, the outer enclosure being provided with the others of the teeth or the pawls,        a plungeable connection with the helical track member for rotation thereof and        a return spring for return movement of the plungeable member on outwards movement of the spout after inwards, dispensing movement.        
Again, the helix of the helical track can be regular. Alternatively the helix of the helical track can be less steep in its portion occupied by the indicator on initial use of the source and steeper in its portion indicating imminent exhaustion of the source.
In accordance with an importance feature, the source includes an end cap of the outer enclosure at its end remote from the spout, the end cap being connected to an outer sleeve of the enclosure, at a position such that dispensing operation of the spout and incrementing operation of the counter are synchronised.
In accordance with a second aspect of the invention there is provided a source of a gaseous, gas borne or droplet substance an inner subassembly and an outer subassembly,                the inner subassembly having:                    an inner pressurised container,            a substance-release valve device sealed across an end of the container,            a spout displaceable inwards of the container against a spring of the valve device for substance release,                            the inner subassembly having an overall length from the distal end of the spout to the remote end of the container, which length decreases on substance release and having at least:                                    a first quiescent length and                    a second length at which the valve is opened for substance release;                                                                                the outer subassembly having:                    an outer enclosure at least partially enclosing the inner container along its length,            an enclosure cap across the end of the enclosure remote from the spout and at least partially at its spout end,                            the enclosure cap and the inner container being arranged to react force for displacement of the spout on substance release;                                    a counter accommodated within the outer enclosure for counting substance release displacements of the spout; and            a counter actuation member arranged beside the spout for displacement inwards to increment the counter                            the outer subassembly having an overall length from the actuation member at the spout to a pressurised-container reaction surface, which length decreases on substance release and having at least:                                    a first quiescent length and                    a second length at which counter incrementation is initiated,                                                                                the subassembly also having:                    a tolerance adjusted connection of the cap to the outer enclosure set with respect to a use installation of the source, whereby the stroke between the first and second lengths of the respective assemblies is compensated for synchronisation of substance release and count incrementation.                        
According to a third aspect of the invention, there is provided a dispenser for a gaseous, gas borne or droplet substance, the dispenser comprising:                a source of the first or second aspect;        a mouth piece in connected to the outer enclosure;        a junction member receiving the spout of the source;        a nozzle connected to the junction member and arranged to direct a dose of the substance out through the mouth piece; and        
means for actuating the dispenser to dispense the dose and increment the counter.
Normally the valve mechanism will be a metered dose valve mechanism.